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Personal: Residential


Basic Terminology Used in the Lighting Industry

American Association for Laboratory Accreditation

Average rated lamp life
Manufacturer's estimate of the length of time 50 percent of any large number of lamps can be expected to last.

An electronic component of every fluorescent fixture. It is used to boost the electric current to start the bulb and to regulate the flow of current to the bulb. An electronic ballast ensures quiet, rapid flicker-free startup and operation. A magnetic ballast, unless ENERGY STAR® qualified, may blink on startup, flicker slightly and/or hum during operation.

Colour rendering index (CRI), accurate colour replication
A measure of how accurately an artificial light source displays colours. CRI is determined by comparing the appearance of a coloured object under an artificial light source to its appearance under incandescent light. The higher the CRI, the better the artificial light source is at rendering colours accurately. A high CRI (above 80) is preferred in the home. All ENERGY STAR qualified fixtures have lamps with a CRI above 80.

Colour temperature
Light bulbs emit varying colours of light. Lighting colour ranges from cool to warm tones, and is known as colour temperature. The colour temperature of a light source indicates the colour of the light emitted measured in degrees Kelvin. Colour temperature is not an indicator of lamp heat. The chart below shows a range of colour temperatures, from warm to cool.

Colour temperature diagram

Having both an electrical and magnetic character or properties

Relying on the movement of electrons in circuits containing semiconductors, resistors or capacitors

Initial performance values
The photometric and electrical characteristics at the end of the 100-hour aging period

Lamp colour
The colour characteristics of a lamp as defined by the colour appearance and the colour rendition

Light output
One of the most important considerations in selecting a light source is how much light it will generate. The unit of measure used for determining light output is the lumen. Light output is measured in lumens at the light source. One lumen equals the amount of light generated by a single standard candle.

Light quality
Having good light quality means using the most efficient light source in a luminaire that integrates with the architectural design.

A measurement of light output. One lumen is equal to the amount of light emitted by one candle that falls on one square foot of surface located one foot away from one candle.

Lumen maintenance
The luminous flux or lumen output at a given time in the life of the lamp and expressed as a percentage of the initial luminous flux. The mean lumens are the value at 40 percent of rated life.

National Voluntary Laboratory Accreditation Program

Power factor
The active power divided by the apparent power (i.e., product of the root mean square [rms] input voltage and rms input current of a ballast)

Private labelled CFL
An ENERGY STAR qualified CFL lamp purchased and marketed under the brand of an ENERGY STAR Participant other than the manufacturer of the product.

Rated voltage
The voltage marked on the lamp

Rated wattage
The wattage marked on the lamp

Rated supply frequency
The frequency marked on the lamp

Rated luminous flux or lumen output
Initial lumen rating (100 hours) declared by the manufacturer

Retired or discontinued product
A product that was properly qualified as ENERGY STAR, no longer manufactured (as of the date on the list), but possibly still available in the market

Run-up time
The time needed for the lamp to reach 80 percent of its stabilized luminous flux after it is switched on

Self-ballasted compact fluorescent lamp (CFL)
A CFL unit that incorporates all elements, permanently enclosed, that are necessary for the starting and stable operation of the lamp and that does not include any replaceable or interchangeable parts

Starting temperature
The minimum and maximum temperatures at which a lamp will reliably start

Starting time
The time needed, after being switched on, for the lamp to start fully and remain lighted

A manufacturer's written promise regarding the extent to which defective goods will be repaired or replaced

A unit of electrical power used to indicate the rate of energy produced or consumed by an electrical device.


The ENERGY STAR name and symbol are administered and promoted in Canada by Natural Resources Canada and are registered in Canada by the United States Environmental Protection Agency.